The invention relates to an aqueous liquid detergent and cleaning agent, containing surfactant(s) and further conventional ingredients of detergents and cleaning agents.
The incorporation of certain active substances (e.g. bleaches, enzymes, perfumes, dyes, etc.) into liquid detergents and cleaning agents can lead to problems. For example, incompatibilities may occur between the individual active components of the liquid detergents and cleaning agents. This can lead to undesired discolorations, agglomerations, odor problems and destruction of detergent active substances.
However, the consumer demands liquid detergents and cleaning agents which optimally display their action at the time of use even after storage and transport. This requires that the ingredients of the liquid detergent and cleaning agent have not settled, decomposed or volatilized beforehand.
By complicated and accordingly expensive packaging, for example, the loss of volatile components can be prevented. Chemically incompatible components can be stored separately from the remaining components of the liquid detergent and cleaning agent and then metered for use. The use of opaque packaging prevents the decomposition of light-sensitive components but also has the disadvantage that the consumer cannot see the appearance and amount of the liquid detergent and cleaning agent.
A concept for incorporating sensitive, chemically or physically incompatible and volatile components consists in using particles and in particular microcapsules in which these ingredients are enclosed so as to be stable during storage and transport.
From the cosmetics sector, British patent GB 1 471 406 describes liquid aqueous cleaning agents which contain at least 2% by weight of triethanolamine laurylsulfate, in total from 8 to 50% by weight of surfactant and from 0.1 to 5% by weight of a suspended phase, for example spheroidal capsules having a diameter of from 0.1 to 5 mm, and have a pH of from 5.5 to 11. A homogeneous distribution of the suspended phase is achieved by using water-soluble acrylic acid polymers, such as, for example, Carbopol 941.
WO 93/22417 discloses liquid cleaning compositions which contain from 5 to 85% by weight of surfactant and from 0.1 to 10% by weight of polymer capsules having a size of less than 250 μm. The polymer capsules contain sensitive cleaning-active substances and polymer compositions consisting of a hydrophobic polymer core and a hydrophilic polymer in a ratio of from 2:8 to 7:3.
WO 97/12027 discloses liquid detergents having a pH of from 5 to 9 (at 10% dilution), which contain from 10 to 40% by weight of anionic surfactants, from 1 to 10% by weight of amine oxides, less than 10% by weight of solvent and from 0 to 10% by weight of electrolyte. The liquid has a viscosity of from 100 to 4000 cps at a shear rate of 20 s−1 and is capable of suspending particles up to a size of 200 μm.
One possibility for suspending particles in a liquid is the use of structured liquids. A distinction is made there between internal and external structuring. External structuring can be achieved, for example, by using structuring gums, such as, for example, xanthan gum, guar gum, carob flour, gellan gum, wellan gum or carrageenan.
From the esthetic point of view, it is desirable for the liquid detergents in which the particles are suspended to be transparent or at least translucent. However, the use of structuring gums often leads to an opaque composition.
The liquid aqueous cleaning agent described in GB 1 471 406 is clear but, owing to the use of the polyacrylate thickener, has no flow limit.
WO 00/36078 describes transparent/translucent liquid detergents which are capable of suspending particles having a size of from 300 to 5000 μm, comprising at least 15% by weight of surfactant and from 0.01 to 5% by weight of a polymeric gum. The Application contains no information about whether the liquid detergents have flow limits. In addition, the liquid detergents described there have only small amounts of fatty acid soaps (≦1.42% by weight).